DESCRIPTION (APPLICATION ABSTRACT): Timely receipt of quality health care is important to the health of America?s children and even more so for children with special needs (CSHCN). However, for children in general and for CSHCN, disparities across vulnerability factors, such as race/ethnicity, SES, and language ability exist in relation to health care access, utilization, experiences, and outcomes. Our conceptual model posits that 1) vulnerability factors are associated with barriers to care, 2) these barriers to care affect access to, use of, and experiences of care, and 3) these barriers to care explain part of the observed health disparities. Developing a measure of barriers to care is a first step in testing this model. The main objective of the proposed research is to identify and measure modifiable barriers to care that affect the link between vulnerability factors, on the one hand, and health care structures, processes, and outcomes for CSHCN on the other. The specific aim of the proposed research is to develop and test a barriers to care questionnaire in English and Spanish. This will be accomplished using focus groups, cognitive interviews, and field testing in an existing sample of vulnerable CSHCN. The proposed research contributes new knowledge, specifically in the conceptualization and operationalization of the construct of barriers to care. Previous research has tended to view barriers to care as unidimensional, has tended to focus on barriers? impact on only one aspect of the health care process, and has tended to view SES and race/ethnicity as explanatory variables. The conceptualization of barriers to care as a multidimensional construct, as potentially impacting children?s health care at several points in the care process, and as distinct from, yet related to SES and race/ethnicity engenders a more robust, practical, and actionable understanding of the construct of barriers to care. A practical, reliable, and valid measure of barriers to care will be useful to many stakeholders in pediatric health care. Such a measure will support consumer choice by giving voice to patients? and parents? experiences with the care system. It will enhance accountability by giving providers and policymakers a tool for comparison and benchmarking. It will spur quality improvement by providing researchers and health care decision-makers a foundation for developing empirically-based interventions to improve the HRQL of vulnerable children. In this way, the proposed research could play a part in contributing to the nation?s goal of eliminating health disparities as described in the Public Health Service?s Healthy People 2010.